JP6103088B2 - Hydrogen filling hose - Google Patents

Description

  The present invention relates to a hydrogen filling hose. More specifically, the present invention relates to a hydrogen filling hose capable of improving pressure resistance and durability while suppressing turbulence of a reinforcing layer at a portion where a hose fitting is tightened and dimensional change due to internal pressure. It relates to hoses.

  In recent years, development of fuel cell vehicles and the like has been actively conducted. Along with this, development of a hose that fills a fuel cell vehicle with hydrogen gas from a dispenser installed at a hydrogen station is also underway. This hydrogen filling hose is required to have excellent hydrogen gas permeability. Further, in order to increase the travel distance of a fuel cell vehicle or the like, it is necessary to fill the fuel tank with hydrogen gas at a high pressure. Therefore, the hydrogen filling hose needs to be practical enough to withstand a high internal pressure of 70 MPa or more. Has been. In order to improve the pressure resistance of the hose, it is a general technique to strengthen the reinforcing layer. However, if a metal reinforcing material is used as a component of the reinforcing layer, it will become brittle by hydrogen, resulting in a short hose life. There is concern about becoming. Therefore, it has been proposed to form all the reinforcing materials by braiding polyparaphenylene benzbisoxazole (PBO) fibers (see Patent Documents 1 and 2).

  A hose fitting made of a nipple and a socket is attached to the end of the hose. When attaching a hose fitting to a hose, generally hold the end of the hose between the nipple and the socket, pressurize the outer peripheral surface of the socket, deform the socket to reduce its diameter, and crimp it. Yes. Since the hydrogen filling hose as described above is required to have high pressure resistance, it is necessary to improve the pull-out resistance and sealing performance of the hose fittings accordingly, and the caulking force increases accordingly. If the caulking force is excessive, the braided structure of the reinforcing layer (particularly the outermost reinforcing layer) is disturbed. In addition, as the amount of hydrogen flowing through the hose increases, the amount of hose dimensional change (expansion and axial contraction, or contraction and axial expansion) increases. The braid structure of the layer tends to be disturbed. Such a disturbance in the braided structure becomes a factor that reduces the pressure resistance and durability of the hose.

  Further, as the pressure of hydrogen increases, the inner surface layer receives a larger internal pressure, so that the dimensional change (expansion deformation, etc.) becomes easier. The inner surface layer in contact with hydrogen becomes brittle because it becomes a low temperature below freezing (for example, about minus 40 ° C.), and damage is likely to occur even if the dimensional change is small. Therefore, in order to improve the pressure resistance and durability of the hose, it is necessary to suppress the dimensional change of the hose.

  A hose provided with a fiber reinforcing layer formed by braiding PBO fibers has excellent pressure resistance and durability. However, in a hose in which the reinforcing layer is composed only of a fiber reinforcing layer braided with such high-strength fibers, it becomes difficult to ensure sufficient pressure resistance and durability when the flowing hydrogen has a higher pressure than before. Since it becomes difficult to suppress the dimensional change of the inner surface layer, improvement is desired.

JP 2010-31993 A JP 2011-158054 A

  An object of the present invention is to provide a hydrogen filling hose capable of improving pressure resistance and durability while suppressing turbulence of a reinforcing layer at a portion where a hose fitting is crimped and dimensional change due to internal pressure.

In order to achieve the above object, in the hydrogen filling hose of the present invention, at least three reinforcing layers are coaxially laminated between an inner surface layer and an outer surface layer that are coaxially laminated, and the inner surface layer is 90 ° C. Gas permeability coefficient of dry hydrogen gas at 1 × 10 ⁻⁸ cc · cm / cm ² · sec. A wire blade in which the outermost reinforcing layer of the reinforcing layer is formed by braiding a metal wire in the hydrogen filling hose formed of a thermoplastic resin of cmHg or less and the outer surface layer is formed of a thermoplastic resin. a layer, other reinforcing layer fiber braid layer der formed by braiding a high strength fiber is, the hose used internal pressure, characterized in that a 45MPa～87.5MPa.

According to the present invention, the inner layer has a gas permeability coefficient of 1 × 10 ⁻⁸ cc · cm / cm ² · sec. Since it is formed of a thermoplastic resin having a hydrogen gas barrier property of not more than cmHg, excellent hydrogen gas permeability can be obtained. Further, since the outermost reinforcing layer is a wire blade layer, even if a hose fitting is strongly caulked at the end of the hose, the braided structure is less likely to be disturbed than in the case of a fiber blade layer. Since the reinforcing layer on the inner peripheral side of the wire blade layer is a fiber blade layer formed by braiding high-strength fibers, it has appropriate pressure resistance. Therefore, even if the hydrogen flowing through the hose becomes a high pressure, the braided structure of the entire reinforcing layer is hardly disturbed.

  Accordingly, the original performance of the reinforcing layer can be sufficiently exhibited, which is advantageous for improving the pressure resistance and durability of the hose. Even if the pressure of hydrogen becomes higher, the dimensional change of the inner surface layer can be suppressed by the reinforcing layer. In addition, an inner layer is formed of a thermoplastic resin having a good hydrogen gas barrier property, and a wire blade layer is disposed as a reinforcing layer on the outermost periphery with a fiber blade layer interposed therebetween. Brittleness is suppressed. This structure also contributes to improving the durability of the hose.

  Here, for example, the inner layer has a thickness of 0.5 mm to 1.5 mm and an inner diameter of 5 mm to 9 mm. According to this specification, it is possible to increase the flow rate of hydrogen while ensuring the durability of the inner surface layer.

  The wire diameter of the metal wire is 0.25 mm to 0.4 mm, the braid angle is 45 ° to 55 °, and the braid density of the wire blade layer is 70% or more. . According to this specification, it becomes easy to ensure the flexibility of the hose and the durability of the metal wire while suppressing the dimensional change of the hose due to the internal pressure.

  The fiber blade layer is at least two layers, the wire diameter of the high-strength fibers constituting the fiber blade layer is 0.25 mm or more and 0.30 mm or less, and the braid angle of the innermost fiber blade layer is 45 °. The specification may be such that the braid angle of the second fiber blade layer on the inner peripheral side is 50 ° or more and 60 ° or less. According to this specification, it becomes easy to ensure the flexibility of the hose and the durability of the high-strength fiber while suppressing the dimensional change of the hose due to the internal pressure.

  Alternatively, the wire diameter of the metal wire is 0.25 mm to 0.4 mm, the braid angle is more than 55 ° and 60 ° or less, and the braid density of the wire blade layer is 70% or more. Can also. According to this specification, it is more and more advantageous to secure the flexibility of the hose and the durability of the metal wire while suppressing the dimensional change of the hose due to the internal pressure.

  The fiber blade layer is at least three layers, the wire diameter of the high-strength fibers constituting the fiber blade layer is 0.25 mm or more and 0.30 mm or less, and the braid angle of the innermost fiber blade layer is 43 °. The braiding angle of the second inner fiber blade layer is 45 ° or more and 55 ° or less, and the third braiding angle of the inner fiber blade layer is 50 ° or more and 60 ° or less. It can also be a specification that is. According to this specification, it becomes easier to secure the flexibility of the hose and the durability of the high-strength fiber while suppressing the dimensional change of the hose due to the internal pressure.

  As the high-strength fiber, for example, polyparaphenylene benzbisoxazole (PBO) fiber is used.

It is a side view which illustrates a hose for hydrogen filling of the present invention by partially cutting it. It is a cross-sectional view of the hose of FIG. It is explanatory drawing which illustrates the dispenser installed in the hydrogen station. It is a side view which illustrates another embodiment of another embodiment of the hose for hydrogen filling of this invention, partially excising.

  Hereinafter, the hose for hydrogen filling of the present invention will be described based on the embodiments shown in the drawings.

  As illustrated in FIGS. 1 and 2, a hydrogen filling hose 1 (hereinafter referred to as a hose 1) of the present invention includes an inner surface layer 2 and a reinforcing layer 3 (first fiber blade layer 3a, 2 fiber blade layer 3b, wire blade layer 3m), and outer surface layer 4 are coaxially laminated. A one-dot chain line CL in FIG. 1 indicates the hose axis.

The inner surface layer 2 has a gas permeability coefficient of 1 × 10 ⁻⁸ cc · cm / cm ² · sec. -It is formed with the thermoplastic resin which is below cmHg. This gas permeability coefficient is a value measured according to JIS K7126. Examples of the thermoplastic resin include nylon (nylon 6, nylon 66, nylon 11, etc.), polyacetal, ethylene vinyl alcohol copolymer, and the like.

  By using a resin having a good hydrogen gas barrier property for the inner surface layer 2 as described above, excellent hydrogen gas permeability can be obtained. The inner diameter of the inner surface layer 2 (that is, the inner diameter of the hose 1) is set to, for example, 4.5 mm to 12 mm, more preferably 5 mm to 9 mm. The larger the inner diameter of the inner surface layer 2 is, the more advantageous is to increase the flow rate of hydrogen H, and the smaller the inner diameter is, the more advantageous is to ensure pressure resistance.

  The layer thickness of the inner surface layer 2 is set to, for example, 0.5 mm to 2.0 mm, more preferably 0.5 mm to 1.5 mm. In order to suppress the dimensional change of the inner surface layer 2, it is preferable to increase the layer thickness. On the other hand, in order to ensure the flexibility of the hose 1, it is preferable to reduce the thickness of the inner surface layer 2. In order to increase the flow rate of hydrogen H while ensuring the durability of the inner surface layer 2, the inner layer 2 may have a thickness of 0.5 mm to 1.5 mm and an inner diameter of 5 mm to 9 mm.

  The outer surface layer 4 is formed of a thermoplastic resin. Examples of the thermoplastic resin include polyurethane and polyester. The layer thickness of the outer surface layer 4 is set to, for example, 0.2 mm or more and 1.0 mm or less, more preferably 0.5 mm or more and 0.8 mm or less. The outer diameter of the outer surface layer 4 (that is, the outer diameter of the hose 1) is set to, for example, 12 mm or more and 18 mm or less, more preferably 15 mm or more and 17 mm or less. As the layer thickness of the outer surface layer 4 increases, it becomes advantageous to ensure the weather resistance of the hose 1, and as the outer diameter decreases, it becomes advantageous to ensure flexibility. In order to achieve both the weather resistance and flexibility of the hose 1, it is preferable to set the layer thickness and the outer diameter of the outer surface layer 4 in the above-described ranges.

At least three reinforcing layers 3 are provided, and one outermost layer is a wire blade layer 3m formed by braiding metal wires m. The other reinforcing layers 3 are fiber blade layers 3a and 3b formed by braiding high-strength fibers f. In this embodiment, the reinforcing layer 3 has three layers, and is configured by laminating two fiber blade layers 3a and 3b and a wire blade layer 3m in order from the inner peripheral side. The fiber blade layers 3a and 3b are not limited to two layers, and may be three layers or more.

  The high strength fiber f is a fiber having a tensile strength of 2 GPa or more. Examples of the high-strength fibers f include polyparaphenylene benzbisoxazole fibers (PBO fibers), aramid fibers, and carbon fibers.

  The wire diameter of the high-strength fiber f is, for example, not less than 0.25 mm and not more than 0.30 mm. The braid angle Af of the first fiber blade layer 3a is, for example, 45 ° to 55 °, and the braid angle Af of the second fiber blade layer 3b is, for example, 50 ° to 60 °. The braid angle Af of the second fiber blade layer 3b is set larger than the braid angle Af of the first fiber blade layer 3a. When there are three or more fiber blade layers, the braid angle Af of the innermost first fiber blade layer 3a is set to 45 ° to 55 °, and the braid angles of the second fiber blade layer 3b and other fiber blade layers Af is set to 50 ° or more and 60 ° or less. And the braid angle Af is set larger as the fiber blade layer is arranged on the outer peripheral side.

  In the case of the fiber blade layers 3a and 3b, since the high-strength fibers f serving as the constituent members are braided in a deformed state (crushed state), it is difficult to define the braid density. Therefore, when the number of driving (the number of high-strength fibers f wound around each reinforcing layer) is defined in place of the braid density, when the outer diameter of the outer peripheral surface around which the high-strength fibers f are wound is 7 mm, the number of driving is, for example, 54 to Ninety. When the outer diameter of the outer peripheral surface around which the high-strength fiber f is wound is 10 mm and 12 mm, the number of driving is, for example, 72 to 120 and 90 to 150, respectively.

  When the wire diameter of the high-strength fiber f is 0.25 mm or more and 0.30 mm or less, it is easy to ensure the flexibility of the hose 1 and the durability of the high-strength fiber f while suppressing the dimensional change of the hose 1 due to internal pressure.

  As the metal wire m, for example, a steel wire, a stainless steel wire, a piano wire or the like is used. The wire diameter of the metal wire m is, for example, not less than 0.25 mm and not more than 0.4 mm, more preferably not less than 0.3 mm and not more than 0.35 mm. The braid angle Am is, for example, 45 ° to 55 °, and the braid density Dm in the wire blade layer 3m is, for example, 70% to 100%, more preferably 80% to 95%. The braid density Dm indicates the area ratio of the metal wire m in the wire blade layer 3m as a percentage, and is 100% when the gap between the metal wires m is zero.

  As the wire diameter of the metal wire m is smaller, it is desirable to increase the braid density Dm so that both the pressure resistance and flexibility of the hose 1 can be achieved appropriately. If the braid density Dm is less than 70%, it is difficult to ensure sufficient pressure resistance. On the other hand, the closer the braid density Df is to 100%, the lower the flexibility, but there is no practical problem. If the wire diameter of the metal wire m is 0.25 mm or more and 0.4 mm or less, the braid angle Am is 45 ° or more and 55 ° or less, and the braid density Dm of the wire blade layer 3m is 70% or more, the dimensions of the hose 1 due to internal pressure It becomes easy to ensure the flexibility of the hose 1 and the durability of the metal wire m while suppressing the change.

  As illustrated in FIG. 3, when the hose 1 is installed in a dispenser 5 installed in a hydrogen station, a hose fitting 6 is attached by crimping to both ends of the hose. Hydrogen H having a low temperature (for example, minus 40 ° to minus 20 °) and high pressure (for example, 45 MPa to 87.5 MPa) is supplied and filled from the dispenser 5 to the vehicle 7 through the hose 1.

  According to this hose 1, since the inner surface layer 2 is formed of the thermoplastic resin having a good hydrogen gas barrier property as described above, it is possible to obtain an excellent hydrogen gas permeability. That is, since the hydrogen H flowing through the hose 1 is sufficiently barriered by the inner surface layer 2, the amount of hydrogen H that permeates to the outer peripheral side of the inner surface layer 2 can be reduced.

  Further, since the outermost reinforcing layer is the wire blade layer 3 m, even if the hose fitting 6 is strongly crimped, the braided structure of the crimped portion of the hose 1 is less likely to be disturbed than in the case of the reinforcing layer braided fiber. And since the inner peripheral side of the wire blade layer 3m is the fiber blade layers 3a and 3b formed by braiding the high-strength fibers f, it has appropriate pressure resistance. Therefore, even if the hydrogen H flowing through the hose 1 becomes high pressure, the braided structure of the entire reinforcing layer 3 is hardly disturbed.

  Thus, even if the reinforcing layer 3 is caulked, the braided structure is not greatly disturbed, so that the original performance of the reinforcing layer 3 can be sufficiently exhibited. Therefore, it is advantageous to improve the pressure resistance and durability of the hose 1. Even if the flowing hydrogen H becomes higher in pressure, the dimensional change of the inner surface layer 2 can be suppressed by the reinforcing layer 3.

  When filling the vehicle 7 with hydrogen H, the hydrogen H at a very low temperature (eg, minus 40 ° C. to minus 20 ° C.) flows in contact with the inner surface layer 2, so that the inner surface layer 2 becomes low temperature embrittled. Moreover, since this hydrogen H is a high pressure (for example, 45 MPa to 87.5 MPa), this pressure acts on the inner surface layer 2 as an internal pressure. Due to the internal pressure, the inner surface layer 2 changes in size but is embrittled at a low temperature. Therefore, even if the amount of small dimensional deformation is not a problem at room temperature, there is a high possibility that the inner layer 2 will be damaged under this use condition.

  Furthermore, since hydrogen H is the smallest molecule, it can penetrate into the inner surface layer 2 relatively easily. Therefore, even if the damage of the inner surface layer 2 is minute, a vicious cycle occurs in which a large amount of hydrogen H enters from that point and the damage becomes increasingly large. Such a specific problem occurs in the hose 1 through which hydrogen H flows.

  In the present invention, as the reinforcing layer 3, in addition to the first fiber blade layer 3a and the second fiber blade layer 3b formed by braiding the high-strength fibers f, the wire blade layer 3m, which has been postponed in the past, is used. ing. The load acting on the hose 1 due to the internal pressure is substantially borne by the first fiber blade layer 3a and the second fiber blade layer 3b. This solves the above-mentioned specific problem.

  And the wire blade layer 3m is made into the structure which does not bear substantially the load which acts on the hose 1 by an internal pressure. Therefore, even if the metal wire m constituting the wire blade layer 3m is hydrogen embrittled, there is no immediate trouble in using the hose 1.

  Since only one outermost layer of the reinforcing layer 3 is a wire blade layer 3m and the other reinforcing layers 3 are fiber blade layers 3a and 3b, the flexibility of the hose 1 is sufficiently secured. As described above, since the wire blade layer 3m does not substantially bear the load acting on the hose 1 due to the internal pressure, it is not necessary to provide the wire blade layer 3m in multiple layers. It also contributes to the development.

  In the embodiment of the hose 1 illustrated in FIG. 4, the reinforcing layer 3 has four layers, and is configured by laminating three fiber blade layers 3 a, 3 b, 3 c and a wire blade layer 3 m in order from the inner peripheral side. Yes.

  The wire diameter of the high-strength fiber f is, for example, not less than 0.25 mm and not more than 0.30 mm. The braid angle Af of the first fiber blade layer 3a is, for example, 43 ° to 55 °, the braid angle Af of the second fiber blade layer 3b is, for example, 45 ° to 55 °, and the braid of the third fiber blade layer 3c. The angle Af is, for example, not less than 50 ° and not more than 60 °. When the braid angle Af of the second fiber blade layer 3b is larger than the braid angle Af of the first fiber blade layer 3a, and the braid angle Af of the third fiber blade layer 3c is larger than the braid angle Af of the second fiber blade layer 3b. Good. For example, the difference between the braid angle Af of the first fiber blade layer 3a and the braid angle Af of the second fiber blade layer 3b is 4 ° or more, the braid angle Af of the second fiber blade layer 3b and the braid of the third fiber blade layer 3c. The difference from the angle Af is preferably 4 ° or more.

  When the fiber blade layers 3a, 3b, 3c are defined in terms of the number of driving (number of high-strength fibers f wound around each reinforcing layer) instead of the braid density, the outer diameter of the outer peripheral surface around which the high-strength fibers f are wound is 7 mm. For example, the number of driving is 54 to 90. When the outer diameter of the outer peripheral surface around which the high-strength fiber f is wound is 10 mm and 12 mm, the number of driving is, for example, 72 to 120 and 90 to 150, respectively.

  The wire diameter of the metal wire m is, for example, not less than 0.25 mm and not more than 0.4 mm, more preferably not less than 0.3 mm and not more than 0.35 mm. The braid angle Am is, for example, more than 55 ° and 60 ° or less, and the braid density Dm in the wire blade layer 3m is, for example, 70% or more and 100% or less, more preferably 80% or more and 95% or less.

  In this embodiment, the braiding angle Am of the metal wire m is larger than that of the previous embodiment, and is set to a static angle (54.7 °) or more. Further, the number of fiber blade layers 3a, 3b, and 3c is set to be larger, and the setting of the braiding angle Af of these fiber blade layers 3a, 3b, and 3c is also different.

  Due to this difference in specifications, the hose 1 of this embodiment has a higher breakdown pressure than the hose 1 of the previous embodiment. Moreover, the dimensional change rate when the internal pressure acts on the hose 1 is further reduced, the dimensional stability is further improved, and the distortion of the inner surface layer 2 can be reduced.

  More specifically, when the internal pressure is applied to the hose 1, the first fiber blade layer 3a and the second fiber blade layer 3b in which the braid angle Af is set to be substantially equal to or less than the static angle have the braid angle Af. The diameter is expanded so as to approach the stationary angle, and the applied internal pressure is efficiently transmitted to the third fiber blade layer 3c and the wire blade layer 3m. Thereby, it becomes possible to make the performance of each reinforcement layer 3 (3a, 3b, 3c, 3m) function in good balance, without the specific reinforcement layer 3 carrying an excessive pressure | voltage resistant burden. In addition to this, the breaking pressure of the hose 1 is improved by the synergistic effect of increasing the number of the fiber blade layers 3a, 3b, 3c and setting the braid angle Af to a predetermined value.

  Further, since the braiding angle Am of the metal wire m is equal to or greater than the static angle (54.7 °), when the internal pressure is applied to the hose 1, the braid angle Am tends to approach the static angle to the wire blade layer 3m. Suppresses the diameter expansion of the hose 1. As a result, the dimensional change rate of the hose 1 is reduced, and the distortion (expansion change) of the inner surface layer 2 can be effectively reduced. Accordingly, the durability of the hose 1 is improved, and it becomes more and more advantageous to extend the service life.

  When hydrogen flows through the hose 1, the inner surface layer 2 becomes a low temperature below the freezing point, so that the inner surface layer 2 becomes brittle at a low temperature and is easily damaged. Therefore, if the diameter expansion deformation of the inner surface layer 2 can be sufficiently suppressed as in this embodiment, the hose 1 is extremely practical.

  In addition, when the rate of change in the dimension of the hose 1 during the internal pressure action is reduced and the change in the longitudinal direction of the hose 1 is suppressed, the hydrogen 1 is supplied from the dispenser 5 to the vehicle 7 and charged with the hose 1. It is difficult to generate unnecessary force in the longitudinal direction. In connection with this, it becomes advantageous also in preventing generation | occurrence | production of the force which is going to produce a malfunction in the connection state between the hose 1 and the hose metal fitting 6.

The analysis model having the same structure as the hose illustrated in FIG. 1 is produced by changing only the specification of the reinforcing layer as shown in Table 1 (Examples 1 to 3, Comparative Example), and the disturbance of the reinforcing layer and the inner surface The amount of change in diameter expansion (size change) of the layer was analyzed and evaluated. The first layer in Table 1 means the innermost peripheral layer, the second layer means a layer laminated on the outer peripheral surface of the first layer, and the third layer means the outermost peripheral layer. The gas permeability coefficient of dry hydrogen at 90 ° C. of the inner layer was 1 × 10 ⁻⁸ cc · cm / cm ² · sec. -It is below cmHg. In addition, test samples were prepared for these four types, and the pressure resistance of the hose assembly in which hose fittings having the same specifications were crimped to the hose ends with the same crimping force was evaluated. The pressure resistance test is a measurement of the breaking pressure in accordance with the method described in JIS K6330-2. These evaluation results are shown in Table 1. The burst pressure was evaluated as an index with a comparative example being 100 as a reference. The larger the index, the better the pressure resistance. The failure mode is also described.

[Disturbance of reinforcement layer]
Hose fittings of the same specifications are attached to the end of the hose with the same caulking force and the blade structure is distorted in the outermost reinforcing layer when the internal pressure of the hose is 80 MPa (up / down fluctuation) Was evaluated as an index using the comparative example as a standard of 100. A smaller index indicates less disturbance.

[Change in diameter of inner layer]
An index evaluation was performed by setting the amount of change in the inner diameter of the inner surface layer under the same conditions as the evaluation of the disturbance of the reinforcing layer as 100 as a reference example. A smaller index indicates a smaller amount of change in diameter expansion.

  From the results in Table 1, it can be seen that Examples 1 to 3 are less disturbed in the braid structure of the outermost reinforcing layer and have a smaller amount of change in diameter of the inner surface layer than the comparative example. In addition, it was confirmed that the hoses of Examples 1 to 3 were able to fully exhibit the original performance of the reinforcing layer because the destruction mode was hose body destruction and had excellent pressure resistance.

Next, as shown in Table 2, in addition to the above-described test sample (Example 3) in which the reinforcing layer was the first fiber blade layer, the second fiber blade layer, and the wire blade layer from the inner peripheral side, Three types of test samples (Examples 4 to 6) in which the specification of the reinforcing layer was changed as shown in Table 2 were made into one fiber blade layer, second fiber blade layer, third fiber blade layer, and wire blade layer. For a total of four types of test samples, the pressure resistance of the hose assembly in which hose fittings with the same specifications are crimped to the end of the hose with the same crimping force and the dimensional change (length change when the hose is pressurized) Rate and outer diameter change rate) and the inner diameter layer expansion change. The gas permeability coefficient of dry hydrogen at 90 ° C. of the inner layer was 1 × 10 ⁻⁸ cc · cm / cm ² · sec. -It was below cmHg. The pressure resistance test is a measurement of the breaking pressure in accordance with the method described in JIS K6330-2. These evaluation results are shown in Table 2. Each evaluation result was evaluated as an index using Example 3 as a standard of 100. The larger the index, the better the pressure resistance, and the smaller the index, the smaller the dimensional change rate and the diameter expansion change amount.

  From the results of Table 2, Examples 4 to 6 are superior in pressure resistance as compared to Example 3, dimensional changes (length change rate and outer diameter change rate) during pressurization of the hose, and inner diameter change of the inner layer. You can see that the amount is small. In addition, it has been found that if the change in diameter expansion (distortion) of the inner surface layer during pressurization of the hose is suppressed, the hose life span becomes longer, and if the change in diameter expansion of the inner surface layer is reduced by about 30%, the hose life span becomes 1 It was also possible to grasp that it was more than 5 times. Therefore, according to Examples 4-6, compared with Example 3, a hose lifetime is significantly improved.

DESCRIPTION OF SYMBOLS 1 Hydrogen filling hose 2 Inner surface layer 3 Reinforcing layer 3a First fiber blade layer 3b Second fiber blade layer 3c Third fiber blade layer 3m Wire blade layer 4 Outer surface layer 5 Dispenser 6 Hose fitting 7 Vehicle f High strength fiber m Metal wire CL hose shaft center

Claims (7)

At least three reinforcing layers are coaxially laminated between the coaxially laminated inner surface layer and outer surface layer, and the inner layer has a gas permeability coefficient of 1 × 10 ⁻⁸ cc of dry hydrogen gas at 90 ° C. · Cm / cm ² · sec. In a hose for hydrogen filling formed of a thermoplastic resin of cmHg or less, and the outer surface layer formed of a thermoplastic resin,
The reinforcing layer of the outermost of the reinforcing layer is a wire braid layer formed by braiding the metal wire, other reinforcing layers Ri fiber braid layer der formed by braiding a high strength fiber, the hose used A hydrogen filling hose characterized by having an internal pressure of 45 MPa to 87.5 MPa .   The hose for hydrogen filling according to claim 1, wherein the inner layer has a layer thickness of 0.5 mm to 1.5 mm and an inner diameter of 5 mm to 9 mm.   The wire diameter of the metal wire is 0.25 mm or more and 0.4 mm or less, the braid angle is 45 ° or more and 55 ° or less, and the braid density of the wire blade layer is 70% or more. The hose for hydrogen filling described.   The fiber blade layer is at least two layers, the wire diameter of the high-strength fibers constituting the fiber blade layer is 0.25 mm or more and 0.30 mm or less, and the braid angle of the innermost fiber blade layer is 45 °. The hydrogen filling hose according to any one of claims 1 to 3, wherein the braiding angle of the second inner peripheral fiber blade layer is 50 ° or more and 60 ° or less.   The wire diameter of the metal wire is 0.25 mm or more and 0.4 mm or less, the braid angle is more than 55 ° and 60 ° or less, and the braid density of the wire blade layer is 70% or more. The hose for hydrogen filling described.   The fiber blade layer is at least three layers, the wire diameter of the high-strength fibers constituting the fiber blade layer is 0.25 mm or more and 0.30 mm or less, and the braid angle of the innermost fiber blade layer is 43 °. The braiding angle of the second inner fiber blade layer is 45 ° or more and 55 ° or less, and the third braiding angle of the inner fiber blade layer is 50 ° or more and 60 ° or less. The hose for hydrogen filling according to any one of claims 1, 2, and 5. The hydrogen filling hose according to any one of claims 1 to 6, wherein the temperature of hydrogen flowing through the hose is minus 40 ° C to minus 20 ° C.

Images